Question

What is innate immunity?

Answer 1

Innate immunity refers to non specific defense mechanisms that come into play immediately or within hours of an antigen's appearance in the body.

Answer 2

Answer

This type of immunity is inborn. This is also called general or natural immunity. This type of immunity does  not give any special protection against any specic germ rather works against all the antigens in the same  way. Hence, it is called general immunity. Following factors facilitate working of innate immunity:

1. Physical Barriers: Physical barriers prevent the entry of germs physically. For example, skin prevents  the entry of many germs and thus works as the rst line of defence. Cilia, in many organs, help in keeping off the germs or other harmful materials.

2. Chemical Barriers: Some germs are warded off by means of chemical barriers. For example,

hydrochloric acid in stomach kills any germ in food.

3. Cellular Barriers: Many special cells eat away germs, e.g. macrophages, neutrophils, etc.

4. Inammation: Inammation and fever also work against germ. The high temperature during fever and  inammation kill the germs.